Milking machine



Aug. 25,. 1942,

R. L. HINMAN MILKING MACHINE Filed June 9, 1939 INVENT [1R HALPH L.HINMAN ATT I] EY Patented Aug. 25, 1942 UNHTED STATES PATENT OFFICEMILKING MACHINE Ralph L. Hinman, Oneida, N. Y.

Application June 9, 1939, Serial No. 278,200

Claims.

This invention relates to improvements in milking machines of the typewhich operate automatically to alternately out off and apply vacuum orpressure to the teat cups.

One of the objects of the invention is to provide a milking machine witha durable simple and economically constructed timer mechanism which willsuccessfully operate without attention throughout extended or prolongedperiods for automatically causing an intermittent suction and releasingaction in the teat cups.

Another object of the invention is to utilize the vacuum adapted toproduce a suction action in the teat cups for actuating the timermechanism.

In carrying out the above mentioned objects, I have produced a timermechanism which is not only self-cleaning but will function without theapplication of lubricant, as grease, to delicately constructed memberssuch as valves, ports, etc. which are readily contacted by dust and dirtusually contained in the atmosphere of a stable. This reduces theliability of the machine functioning improperly or failing to functionaltogether after having been in operation for a few hours and eliminatesthe frequent cleaning of such parts of the timer.

Another object of the invention is to provide a timer of the abovementioned class wherein the number of pulsations per minute aremaintained substantially uniform from day to day without the aid ofmanually adjustable control members. This necessity of adjustment of thetimer in order to maintain maximum efficiency in the operation of themilking machine has heretofore been a source of annoyance andinconvenience to operators of milking machines, to say nothing of theexpense and time consumed in making such adjustments.

A still further object of the invention is to provide a timer having apiston provided with a yielding or pliant packing or valve membercomposed of leather or the like with means for maintaining said packingmember in sealed relation with the wall of the piston chamber.

I attain these objects by mechanism illustrated in the accompanyingdrawing, in which:

Figure 1 is a perspective view of a milking machine embodying thevarious features of this invention.

Figure 2 is an enlarged detail vertical sectional view through the upperportion of a pail, a cover therefor and a timer mounted on said cover,taken substantially in the plane of the line 2-2, Figure 1.

Figure 3 is a fragmentary, sectional view takeri on line 3-3, Figure 2.

My invention, as illustrated in the drawing, comprises primarily a pailH], a cover ll, an automatic timer I 2 connected with the cover H forcontrolling the pressure pulsations in the milk tube and teat cups and acluster of teat cups l3,

Pail

The pail H], as shown, comprises a cylindrical body portion 15 and aconical neck portion I6 connected with the upper end of the body portion[5. The pail I0 is provided with a handle l8 which, in this instance,comprises a rod bent substantially U-shaped. The rod may be connected atits ends with the body portion l5 and neck portion [6 in any suitablemanner as by electric welding.

Cover The cover H is, as usual in milking machines of this character,removably mounted on the upper end of the pail I0 and is adapted to bemaintained in air-tight connection with the pail by means of a resilientwasher 2i removably secured in an annular recess provided in the lowerface of the cover H. The cover H, as shown in Figure 2, is provided withthe usual milk delivery nipple 23 secured to the cover in communicationwith the interior of the pail ID. A flexible tube 24, having one endmounted on the nipple 23, is connected at its other end to the manifold25 of the usual claw member 26 which is connected in a suitable mannerto the interior of the teat cup inflations. The cover H is also providedwith a nipple 27 which is secured to the outer face of the cover H inspaced relation to the nipple 23 with the interior thereof extendingthrough said cover. A flexible hose 28, having one end mounted on thenipple 21, is adapted to be connected at the other end with a convenientair exhausting device (not shown) for maintaining a partial Vacuum inpail l0.

Timer in substantially concentric relation ther with.

Mounted on the plate 3! is a second cylinder 34 of greater diameter thanthe cylinder 39. The cylinder 34 is removably secured to the plate 3! insubstantially coaxial relation therewith by a pair of diametricallydisposed pins secured to the flange 32 and which extend inwardly throughcorresponding T-slots 3 3 provided in the cylinder 34 at the lower edgethereof. The outer end of the cylinder 34 has removably connectedthereto a head 38, as by screw-threads 35'. The head 36 has acylindrical housing 3? connected therewith to extend outwardly therefromand which provides a valve or inlet chamber 38 arranged substantiallycoaxially with the interior of the cylinders 39 and 3 3. Theouter end ofthe housing 3'! is closed by a cap 3% having screwthreaded engagementwith said housing.

The valve chamber 38 is provided with a valve seat to arrangedintermediate the ends thereof. A valve El, mounted in the outer endportion of the valve chamber 38, is adapted to move into and out ofengagement with the seat 48. The valve M is provided with a stem 42which extends inwa'rdly from said valve through the inner end portion ofthe valve chamber 38, through an aperture 5-3 provided in the head 38substantially centrally thereof and into the chamber All of cylinder 34.

Mounted in the cylinder chamber 54 is a piston 43 comprising a flexibledisk valve or packing t? having a laterally disposed marginal flange ii?adapted to have air-tight contact with the wall of the cylinder chamber54. the central portion thereof supported between a pair of rigidwashers or plates 49. The piston 46 is removably secured to one end of atubular sleeve or connecting rod 5| by means of a flanged screw 52extending downwardly through central apertures provided in the plates 29and valve ill into screw-threaded engagement with the interior of thesleeve 5!. The screw 52 also coacts with the sleeve 5| for securing theplates i9 and valve 5'! to each other. The sleeve or connecting rod 5|extends downwardly from the piston 66 into the interior of cylinder 33and is provided at its lower end with a piston 54 reciprocati'velymounted in the cylinder 86. k

The inner chamber 55 of the sleeve St has the lower end thereof closedby the end wall 55 of piston 54. The upper end of the sleeve 55 issubstantially closed by the hereinbefore mentioned screw 52 which isprovided with a central aperture 51 through which the valve stem 62ext'eh'ds. Mounted in the chamber 55 is a spring '59 which contacts atits lower end with the wall 56 and has the upper end thereof inengagement with the head it of a trip pin 5! for yieldingly' urging thepin toward the upper end of sleeve 53.

The wall 55 of the piston 53 is provided with a centrally disposedaperture 62 adapted to maintain the interior 55 of sleeve '5! incommunication with the lower end portion of cylinder 3!! and, therefore,with the interior of the pail ii). In order that the aperture 52 willnot be closed when the trip pin 6| is in'it's lowermost position, thelower end of said trippin is provided with diametrically disposedrecesses '01" grooves 63. Likewise, the upper face of the head 53 may beprovided with diametrically disposed recesses or grooves 64 so that ifsaid head comes into contact with the lower end 'of the screw 52, theaperture 51 through said screw will not become sealed by said head.

The valve 47 has The cylinder 30 is provided with a laterally disposednipple 63 communicating with the interior of said cylinder substantiallymidway between the ends thereof. A flexible tube 61 is connected at oneend to the nipple 66 and has the other end thereof connected to themanifold 25 of the claw 28 which, in turn, is connected by tubes 58 withthe interior of the shells of the teat cups l3.

' Mounted in the lower end of the cylinder 34 adjacent the end plate 3|is an expander ring 10 which is removably connected with the cylinder 34by a pair of diametrically disposed pins H secured to said ring andwhich extend outwardly into the adjacent T-slots 35- provided in thelower end of the cylinder 35. The ring l0 has the upper cuter marginaledge thereof tapered inwardly, as at 19' to form a cam surface adaptedto be engaged by the lower edge of the flange d8 of the piston valve 31for pressing said flange outwardly against the inner Wall of thecylinder 34 when the piston 15 is in its lowermost position and therebymaintaining the valve A1 in air-tight sealed relation with the cylinder35.

It will now be understood that when vacuum is maintained in the pail It)by the connection of the tube 23 with a suitable air exhausting device,the end portion of the cylinder 35 beneath the piston 54 will also bemaintained under vacuum. It also follows that inasmuch as the cylinder39 is maintained in communication with the upper end portion of thecylinder 34 by the air passage provided by the aperture 51 in screw 52,chamber 55 of the sleeve 5i and the aperture 62,.vacuum will also benormally maintained in the upper end of the cylinder 34. Likewise, thelower or inner end of the valve 4! will be maintained under theinfluence of vacuum due to the connection of the lower portion of thevalve chamber 38 with the interior of the cylinder 34 by theaperture'dii.

The outer end portion of the valve chamber 38 is maintained in permanentcommunication with the outside atmosphere by apertures 13 provided inthe wall of the housing 31 beneath the cap 39. It therefore follows thatthe valve AI will be maintained in engagement with the seat 4t] by thedifferent fluid pressures provided atppposite sides of the valve.

When the valve assembly consisting of the pistons 45 and 54 and theconnecting means therefor is in its lowermost position,'the line ofcommunication between the nipple ts and the interior of the pail Iiiwill be closed by the piston valve Eddue to said valve being locatedbeneath the inlet of the nipple 65-, as indicated by broken lines inFigure 2. The lower portion of the cylinder 34 is maintained incommunication with the outside atmosphere by openings 75 provided in theend plate 3!, so that when the piston valve 54 is in its lowermostposition, atmospheric pressure is admitted from the interior of cylinder34 through the upper portion of the cylinder 30 to the interior of thenipples 66 and thence to the interior of the teat cup shells through thetube El and tubes '68-.

I Assuming now that the piston assembly is in it's lowermost positionand that the valve 11 is in a, closed position in engagement with theseat 40, air in the lower portion of the valve chamber 38 beneath thevalve ll and in the upper .portion of the cylinder '34 above the pistondo will be drawn downwardly, through the interior of the tube 5| andaperture 62 into the pail 11L As the vacuum thus produced in thecylinder 34 approaches the value of the vacuum in the pail ID, theaction of the vacuum upon the piston 46, due to the area of said pistonbeing greater than that of piston 54, will overcome the action of thevacuum on said latter piston, thereby causing the valve assembly to moveupwardly through the cylinders 3|! and 34. The upward movement of thepiston 54 will first close the opening of the nipple 65, after whichsaid nipple will be brought into communication with the interior of thepail I!) as the opening to the nipple is uncovered by valve 54 andthereby bring the interior of the shells of teat cups connected with thenipple 66 under the influence of the vacuum in the pail I0.

During the initial upward movement of the piston assembly, the lower endof the valve stem 42 will be engaged by the trip pin 6| due to said trippin being yieldingly maintained in its uppermost position by the spring59. However, the valve 4| will not be moved from its closed position inengagement with the seat 45 by the trip pin and spring due to the actionof the differential fluid pressure upon the valve 4i being greater thanthe action of the spring 55. As the piston assembly continues its upwardor outward movement the trip pin 6| is engaged by the lower wall 56 ofthe chamber 55 and valve 45 will be positively moved from its seat 48 bythe coaction of the wall 56, trip pin 6| and valve stem 42.

As soon as the valve 4| is moved out of engagement with the seat 40, airunder atmospheric pressure passes through aperture 33 into the valvechamber 38 and then downwardly around the valve 4| through the aperture43 into the upper end of cylinder 34. As the vacuum in the cylinder 34is thus relieved, the valve assembly will be moved to its lowermostposition by the action of the vacuum in the pail l upon the lower end ofthe piston valve 54.

The relative effective sizes of the apertures 43 and 62 are such thatthe vacuum in the cylinder 34 is gradually relieved so that the pistonassembly is moved downwardly at substantially the same speed as that ofthe upward movement of said assembly and thereby maintain asubstantially uniform operation of the milking machine. It is preferablethat the size of the aperture 62 and the effective size of the aperture43 are relatively small so as to maintain a high degree of efiiciency inthe operation of the machine. The sizes of apertures 43 and 52 not onlymaintain the amount of air drawn downwardly through the timing mechanismand out through the tube 28 at a minimum but also cause the air to movewith such velocity through the aperture 43 around the valve stem 42 andthrough the aperture 62 as to maintain these elements practically freefrom dirt.

The aperture 43 is not only maintained clean and free from dirt by thepassage of air therethrough but also by the excessive vertical move mentof the valve stem 42 produced by the action of the spring 59thereonafter valve 4| is moved from its seat 40 by the piston assemblyand trip pin 6|, said action of the spring causing the valve 4| to moveupwardly from the seat 40 into engagement with the cap 39. As the pistonassembly moves downwardly, the valve 4| will be maintained in itsuppermost position in contact with the cap 39 by the spring 53 untilsaid spring is fully extended, whereupon the head 60 of the trip pin BIis only slightly spaced from the inner end of screw 52.

As the valve assembly continues its downward movement after the spring59 is extended, the valve 4| will move downwardly with said assemblyuntil the valve again engages seat 40. As soon as the valve 4| is in itsclosed position, the upper end of cylinder 34 is cut off fromcommunication with the outside atmosphere, with i said piston overcomesthe action of the vacuum in the lower end of cylinder 38 upon the piston54 and causes the valve assembly to begin its upward movement.

It will now be noted that the differential fluid pressure upon thepiston assembly caused by action of vacuum in pail H1 upon piston 54 andatmospheric pressure on valve 41, when valve 4| is open, not onlyproduces the down stroke of the piston assembly but also causes. flange48 of piston valve 41 to engage the tapered or cam surface Hi of ringIt]. This engagement of flange 48 with ring ID is of sufficient force topress the flange outwardly against the wall of cylinder 34 so that atthe beginning of each up stroke of the piston assembly the piston valve41 is in sealed contact with cylinder 34.

These cycles of operation of the valve assembly may continue as long asvacuum is produced in the pail It! to intermittently bring the teat cupsl3 under the influence of the vacuum in the interior of the pail H] andwith the outside atmosphere through the medium of the timing mechanism.

Although I have illustrated and described in detail the preferredembodiment of my invention, I do not Wish to be limited to the exactconstruction shown as various changes in the form and relation of theparts thereof may readily be made without departing from the spirit ofthe invention as set forth in the appended claims.

I claim:

1. In a timing mechanism for a milking machine or the like, a cylinder,a piston slidably mounted in said cylinder having a resilient sealingmember engageable with the wall of the cylinder for maintainingfluid-tight connection between the piston and cylinder, and means withinsaid cylinder and engageable with said sealing member at a predeterminedposition in the stroke of the piston for intermittently moving saidsealing member into pressure engagement with the Wall of the cylinder.

2. A structure as defined in claim 1 wherein the sealing member includesa marginal flange disposed substantially coaxially with the cylinder,and said means includes a ring having a tapered surface engaged by saidflange for urging the latter into engagement with the cylinder wall.

3. In a milking machine, the combination with a receptacle having avacuum chamber, of a pulsator comprising a casing connected with saidreceptacle and defining a pair of piston chambers of unequal diametersarranged in vertical relation one above the other, the smaller of saidpiston chambers being in direct communication with said vacuum chamberand having a part adapted to be connected with a set of teat cups, areciprocating timer valve mechanism mounted in said casing including apair of pistons, one

piston for each chamber, the piston in said smaller piston chamber beingadapted to control communication of the cups with said latter chamberfor alternately bringing the cups into communication with the receptaclevacuum chamber and with the outside atmosphere, said pistons beingconnected to reciprocate in unison and having a restricted passagetherethrough maintaining the upper end of the larger chamber incommunication with the lower end of the smaller chamber, said casinghaving an air inlet passage connecting the upper end of the largerpiston chamber with the outside atmosphere, a vertical reciprocatingvalve in said passage adapted to be maintained in the closed position bydifferential air pressure, and means including a spring actuated by thepistons at a predetermined position in the upward stroke of said pistonsfor opening said valve and maintaining the same in the open positionduring the greater portion of the downward stroke of said pistons.

4. In a milking machine, the combination with a receptacle having avacuum chamber, of a pulsator comprising a casing connected with saidreceptacle and defining a pair of piston chambers of unequal diametersarranged in vertical relation one above the other, the smaller of saidpiston chambers being in direct communication with said vacuum chamberand having a part adapted to be connected with a set of teat cups, areciprocating timer valve mechanism mounted in said casing including apair of pistons, one

piston for each chamber, the piston in said smaller piston chamber beingadapted to control communication of the cups with said latter chamberfor alternately bringing the cups in communication with the receptaclevacuum chamber and with the outside atmosphere, said pistons beingconnected to reciprocate in unison and having a bore extending inwardlyfrom the upper end of the larger piston, said casing having an air inletpassage connecting the upper end of the larger piston chamber with theoutside atmosphere, and a vertical reciprocating valve'in said passageadapted to be maintained in the closed position by differential airpressure, said valve having a stem loosely received in said boreengageable with the lower end of the bore ata predetermined position inthe upward stroke of said pistons for opening said valve'against theaction of said air pressure, said pistons being provided with arestricted passage maintaining the bore in communication with the lowerend of the smaller piston chamber whereby the upper end of the largerpiston chamber is maintained in constant communication with the vacuumin said lower end of said smaller chamber.

5. In a timing mechanism for a milking machine or the like, thecombination with a vacuum chamber adapted to be connected with a sourceof suction; of a casing means defining a pair of piston chambers ofunequal diameters arranged in vertical relation one above the other, thelower end of the smaller of said piston chambers being in directcommunication with said vacuum chamber; said casing means having amember defining a passage extending laterally from said smaller pistonchamber adapted to be operativelyiconnected with a set of teat cups orthe like; a reciprocating timer valve means mounted in said casing meansincluding a pair of pistons, one piston for each piston chamber, saidpistons being connected to reciprocate in unison and the piston in saidsmaller chamber being adapted to control communication of said lateralpassage with said latter chamber for alternately bringing said passagein communication withthe vacuum chamber and with the outside atmosphere;said casing means also having an air inlet passage connecting the upperend of the larger piston chamber with the outside atmosphere; and avertical reciprocating valve member in said air inlet passage adapted tobe maintained in the closed position by differential air pressure, saidvalve member and said timer valve means having mechanical elementscoacting at a predetermined position in the upward stroke of said valvemeans for opening said valve member against the action of the saiddifierential air pressure; one of said means having a fiuid conveyingmeans associated therewith defining a restricted valveless air passagemaintaining the upper end of the larger piston chamber in constantcommunication with the vacuum in the lower end of said smaller pistonchamber.

RALPH L. HINMAN.

